what is the problem in js line 4

Question

in Javascript
https://code.sololearn.com/WBPJXCL1ooHw/?ref=app

Answer 1

//Nothing wrong just write it in same html tab under body tag
https://code.sololearn.com/WcO4fVhtF96S/?ref=app

Answer 2

https://www.sololearn.com/post/90825/?ref=app

Answer 3

Hello! You can put your js code in this block (js section):

Window.onload = () =>
{
>>>>put your all js code here<<<<
}